优化类型的定义

to_int64.go

@@ -8,34 +8,41 @@ import (
 // interface 转 int64
 func ToInt64(val interface{}) (i int64, err error) {
 
-	if v, ok := val.(int64); ok {
-		i = v
-	} else if v, ok := val.(int32); ok {
-		i = int64(v)
-	} else if v, ok := val.(string); ok {
-		// string 转 int64
-		// 第二个参数为基数（2~36），第三个参数位大小表示期望转换的结果类型，其值可以为0, 8, 16, 32和64，分别对应 int, int8, int16, int32和int64
-		i, err = strconv.ParseInt(v, 10, 64)
-	} else if v, ok := val.(float64); ok {
-		i = int64(v)
-	} else if v, ok := val.(float32); ok {
-		i = int64(v)
-	} else if v, ok := val.(int); ok {
-		i = int64(v)
-	} else if v, ok := val.(uint); ok {
-		i = int64(v)
-	} else if v, ok := val.(uint32); ok {
-		i = int64(v)
-	} else if v, ok := val.(uint64); ok {
-		i = int64(v)
-	} else if v, ok := val.(bool); ok {
+	switch v := val.(type) {
+	case int:
+		return int64(v), nil
+	case int8:
+		return int64(v), nil
+	case int16:
+		return int64(v), nil
+	case int32:
+		return int64(v), nil
+	case int64:
+		return v, nil
+	case uint:
+		return int64(v), nil
+	case uint8:
+		return int64(v), nil
+	case uint16:
+		return int64(v), nil
+	case uint32:
+		return int64(v), nil
+	case uint64:
+		return int64(v), nil
+	case float32:
+		return int64(v), nil
+	case float64:
+		return int64(v), nil
+	case nil:
+		return 0, nil
+	case string:
+		return strconv.ParseInt(v, 10, 64)
+	case bool:
 		if v {
-			i = 1
+			return 1, nil
 		} else {
-			i = 0
+			return 0, nil
 		}
-	} else {
-		err = errors.New("不支持的参数类型")
 	}
-	return
+	return 0, errors.New("convx.ToInt64: unknown type")
 }